I had the same problem mentioned here.

I uninstalled just the Java2 piece that was installed with LimeWire and my problem went away ... but, of course, I could then not run LimeWire.

Went to the Sun Microsystems Site to try a latest Java2.
I installed version 1.3.1.04 from their site. LimeWire works and I have not seen the ie6 crash problem since.